This activity is designed to allow Typemock Isolator based tests to be run inside a TFS 2010 Team Build. This activity is required because you have start Isolator’s mocking interceptor before you run any tests that use Typemock (and stop it afterwards). If
you are running in the Visual Studio IDE this is all done automatically, but is not done as part of an MSBuild Team Build Process by default.

The problem with Team Build 2010 is that you no longer get this single MSBUILD file to manage the whole Team Build, it is now a XAML workflow. In the past the single MSBUILD file ran in a single process, so you could start and stop the mocking tools as you
required, and be sure they were running when you needed them. Under the new workflow model each activity is its own process (and can potentially be run in parallel). So to make sure mocking intercepting is running at the right time it must be handled atomically
with running MSTest. This can only currently be achieved by wrapping the call to MSTest.EXE inside Typemock’s TMOCKRUNNER.EXE.

This activity actually provides a generic external test runner that takes most of the standard parameters passed to the MSTest activity and transforms them such that they can be used by TMOCKRUNNER. Though designed for the purpose of running Typemock Isolator,
there is no reason that this activity could be used for any task that requires one executable to be wrappered in another.